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 A030631 Numbers with 13 divisors. 27

%I

%S 4096,531441,244140625,13841287201,3138428376721,23298085122481,

%T 582622237229761,2213314919066161,21914624432020321,

%U 353814783205469041,787662783788549761,6582952005840035281

%N Numbers with 13 divisors.

%C 12th powers of primes. The n-th number with p divisors is equal to the n-th prime raised to power p-1, where p is prime. - _Omar E. Pol_, May 06 2008

%C Solutions of the equation n'=12*n^(11/12), where n' is the arithmetic derivative of n. - _Paolo P. Lava_, Oct 31 2012

%H R. J. Mathar, <a href="/A030631/b030631.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n)=A000040(n)^(13-1)=A000040(n)^(12). - _Omar E. Pol_, May 06 2008

%t (Prime@Range@30)^12 (* _Vladimir Joseph Stephan Orlovsky_, Apr 11 2011 *)

%o (MAGMA) [p^12: p in PrimesUpTo(100)]; // _Vincenzo Librandi_, Mar 27 2014

%o (PARI) is(n)=isprimepower(n)==12 \\ _Charles R Greathouse IV_, Jun 19 2016

%Y Cf. A000040, A030629.

%Y Subsequence of A008456.

%K nonn,easy

%O 1,1

%A _Jeff Burch_

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Last modified December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)